#pragma once
#include "hd2d/Camera.h"
#include "hd2d/Scene.h"
#include "hd2d/SpriteAtlas.h"
#include "hd2d/Weather.h"

#include <array>
#include <random>
#include <string>
#include <vector>
// Meadow diorama: terraced grass, a cliff ridge with steps, a pond crossed by
// a stone bridge with burning braziers, 3D trees/bushes/rocks, weather and a
// WASD-controlled pixel-art player sprite.
class DemoScene {
public:
    bool load(const std::string& assetDir);
    // `move`: x = screen right, y = screen up (camera-relative), length <= 1.
    void update(float dt, float time, glm::vec2 move, const hd2d::Camera& camera);
    void placePlayer(glm::vec2 xz);

    hd2d::Scene scene;
    glm::vec3 playerPos{0.0f};
    hd2d::Weather weather;  // call weather.update() each frame before rendering

    // Billboard feature test (`--sprite-test`; set before load()): a row of
    // atlas / sprite-sheet sprites behind the player exercising sub-rect
    // frames, flip, turn, alpha dither and flash. Labels are world-space
    // points (sprite tops) for the caller to draw.
    bool spriteTest = false;
    struct Label {
        glm::vec3 pos;
        const char* text;
    };
    std::vector<Label> labels;

private:
    struct Obstacle {
        glm::vec2 pos;
        float radius;
    };
    bool buildSpriteTest(const std::string& assetDir);
    void updateSpriteTest(float time, const hd2d::Camera& camera);
    void buildTerrain();
    void scatterProps();
    bool walkable(glm::vec2 from, glm::vec2 to) const;
    bool occupied(glm::vec2 p, float r) const;
    float groundHeight(glm::vec2 p) const;  // terrain or bridge deck

    hd2d::Terrain terrain_;
    hd2d::Water water_;
    hd2d::ParticleSystem particles_;
    hd2d::BillboardBatch tallGrass_, tufts_, flowers_, player_;  // pixel-art sprites
    hd2d::ModelLibrary models_;                                  // 3D scenery
    std::array<hd2d::ModelBatch, 2> oaks_, pines_, bushes_, rocks_;  // two model variants each
    hd2d::ModelBatch bridge_;
    hd2d::GroundOcclusion groundAO_;
    std::vector<Obstacle> obstacles_;
    std::vector<unsigned char> tallGrassMask_;
    std::mt19937 rng_{42};
    float playerSpeed_ = 4.2f;
    float walkPhase_ = 0.0f;
    hd2d::SpriteAtlas atlas_;           // sprite test: runtime-packed cells
    hd2d::BillboardBatch atlasSprites_;  // uses atlas_.texture() via sharedTexture
    hd2d::BillboardBatch sheetSprites_;  // own texture: a 2x1 sheet read with Texture::cellUV
    int atlasSlots_[3] = {-1, -1, -1};   // hero, flowers, tuft
    int sheetFeetRows_[2] = {0, 0};      // per sheet cell, from the cell top
    float stepTimer_ = 0.0f;
    float facing_ = 0.0f;
};